Establishing and maintaining a defined thermal metabolism is of great significance with infants and has substantially determined the development of incubators, heated beds and radiation heaters.
Generally, a rectal or localized skin temperature known in advance is not adequate for defining the thermal condition and for metering the applied thermal energy. These measured values are not sufficiently definitive with respect to the overall thermal metabolism of the infant and it is therefore an object of the invention to provide a method which provides an overall view of the thermal balance of the infant and of its condition (hypothermia, neutral behavior, fever, shock, etc.). It is another object of the invention to provide this overall view with the least possible ancillary means.
Published German patent application DE-OS 36 16 359 discloses an incubator having radiant heaters. A sensor device for the more important parameters such as air temperature, air humidity, skin temperature, pulse frequency and the like are also disclosed. An alarm device is provided to directly indicate any deviation from the permissible range of the parameters. However, such a monitoring method does not provide adequate knowledge of the temperature zones determining the thermal metabolism and the control of the operating parameters is therefore essentially determined by arbitrarily selected desired values.